how to control the characters in Sims 4. Help

My daughter has been building a sims world and was doing well. However, her 7 yr old sister has done something and the characters no longer do as she tells them, eg one character is hungry but wont respond to the command to have a quick snack. Another is "late for work" but wont get out of bed etc.

She is (understandably) quite upset so I was wondering if anybody might know what my mini beast has done to **bleep** up the controls and what I can do to make the game characters start responding again.

Many thanks,

P